The fans need to give Onana a little chance to give his best for his chance to develop at the Red Devils, of course a little patience to find confidence again from being down after joining the Red Devils, and it's very different when Bermian was at Inter Milan, in fact he played very impressively so everyone needs the process of returning to his best form, has been very visible from the several occasions that Onana has played in several important matches for the Red Devils, sometimes defenders and goalkeepers have to have the same chemistry to secure the ball, but it is very clear that in several important matches they don't So visible this season for the Red Devils..
Of course he should be giving a chance to prove his worth because is obvious that he has seriously improved in performance lately unlike his early time on Manchester United when he was finding it very difficult to perform due to the fact that he was new and not use to the club method of playing which I believe is normal for any goalkeeper who finds himself on a new club so is obvious that before he could plend to the pattern of the team will take some time.
But now Onana has started proving himself that he is a good goalkeeper because considering there past matches he has save Manchester United several times so I believe that if they give him some more time he is going to explore more of his potential to Manchester United so perhaps I'm beginning to see the good performance in him.